JP6290435B2 - Grounding system for high voltage semiconductor valves - Google Patents

Description

  The present invention relates to a grounding system for a high voltage semiconductor valve.

  Periodic maintenance and / or adjustment may be required in valve holes where high voltage semiconductor valves may be arranged to hang from the ceiling. No worker should be in the valve hole when voltage is applied to the valve. In order to allow an operator to enter the valve hole for some purpose such as maintenance, it is necessary to release the voltage applied to the valve. In order to avoid discharge from the bulb such as a surge current blow or corona discharge from residual capacitor charge or static charge in insulating the material when the worker must enter the valve hole in a safe condition The valve needs to be connected to the ground. This is because they may cause harm to workers in the valve hole. In order to minimize the risk of partial discharge and / or flashover, so-called corona shields are used in existing bulbs to lower the electric field. A shield is placed around the outer surface of the bulb. Discharge and spontaneous discharge can also occur when the application of voltage to the bulb is released. Corona discharge is a continuous partial discharge that occurs near a highly stressed bulb. Corona discharge depends, among other things, on humidity and density in the atmosphere, voltage levels, and distance to nearby objects.

  It is known to provide valve grounding when the valve hole is opened and accessible to maintenance personnel and the general public, and thus when the voltage is removed from the valve. Ground is used to ensure that residual charge in the system or arrangement, for example from the capacitor, is discharged. For such grounding purposes, the operator must enter the valve hole and manually install the grounding contact. Such a ground contact must first be moved to the correct position and then connected to a plug or socket in the valve hole floor and then extended to establish electrical contact with the valve. These steps are close to the actual ground contact or at least within the valve hole, since the ground contact must be moved to the correct position, connected to the plug, and extended to make electrical connection with the valve. Must be implemented by. Residual charge or spontaneous discharge in the capacitor can occur during these steps and can be harmful to the operator. Furthermore, as is the case whenever human work is involved, manual steps during such grounding operations increase the potential risk of failure or error. There are a plurality of valves in the valve hole. Furthermore, the manual steps described above are time consuming and therefore expensive.

  Accordingly, it is an object of the present invention to provide an improved grounding system for high voltage semiconductor valves.

  This object is achieved by a high voltage valve configuration comprising a high voltage valve unit, an external electrical shielding structure disposed at least partially around the high voltage valve unit, and a grounding system. The grounding system includes a stretchable grounding device configured to extend from a remote location so that it can be moved from a retracted position to an extended position, and the extendable grounding device is configured to extend when retracted from the retracted position. Establish electrical connection with external electrical shielding structure.

  A stretchable grounding mechanism can be automatically stretchable by operation from a remote location. Therefore, it can be controllable by operation from a remote location. The remote location can even be outside the valve hole.

  Advantageously, the high voltage valve arrangement comprises a plurality of guide elements, which are electrically connected to the electrical shielding structure so that the extendable grounding device is in the extended position when in the extended position. Configured to establish an electrical connection with at least some of them. The grounding system of the present invention has the advantage of being reliable, safe and economical.

  The guide element or at least the surface of the guide element is made of a conductive material.

  There can be more than one stretchable grounding device installed per valve. The shielding structure protects the lower surface and the four side surfaces of the bulb, which provides four extensible grounding devices per bulb, one for each side surface.

  Alternatively, the entire shielding structure and all its elements can be electrically interconnected, so that a single grounding system per valve is sufficient.

  In one embodiment, the extendable grounding device may be configured to be mounted to extend vertically downward from the retracted position to the extended position and vertically upward from the extended position to the retracted position. This can provide additional safety in rare cases where power is completely cut off or a power outage occurs. In such cases, the drive of the extensible grounding device, etc. no longer works and therefore gravity can be used to place the extensible grounding device in place and thus ground the electrical shielding structure.

  The stretchable grounding device can be configured to be attached to the ceiling of the structure. This simplifies installation and installation, since the bulb is usually also mounted to hang from the ceiling. Alternatively, the grounding system and extendable grounding device can be configured to be connected to the valve transport structure so that the valve can be installed as a package with the grounding system.

  Preferably, at least some of the guide elements are funnel shaped. This facilitates the movement of the extendable grounding device during the extension operation from the retracted position to the extended position. Furthermore, it ensures that each part or element of the electrical shielding structure is electrically connected to the extensible ground system via the guide element.

  In one embodiment, at least some of the guide elements are funnel shaped at both ends and are therefore more widened at the top and bottom than the middle. This shape will facilitate the movement of the extendable grounding device during the retraction or withdrawal operation from the extended position to the retracted position.

  In one embodiment, the stretchable grounding device can comprise a surge current limiting resistor at its free end. The free end of the stretchable grounding device is the end opposite the ceiling of the structure when the HVDC (high voltage direct current) valve configuration is hanging, and is therefore the end directed to the floor of the structure .

  Placing the surge current limiting resistor at the free end of the stretchable grounding system means that the surge current limiting resistor always first contacts the guide element and thus contacts the electrical shield of the electrical shielding structure. Ensure that it is the first element of a stretchable grounding device. This ensures that some residual capacitor energy is consumed by the resistor during the grounding process and sequence.

  The stretchable grounding device comprises a low resistance wire and a winch so that the low resistance wire is wound up by the winch so that the winch moves the low resistance wire from the retracted position to the extended position and returns it. Composed.

  Using a low resistance wire in conjunction with the winch has the advantage that the winch is easily remote controlled and the wire has a very low electrical resistance, thereby providing some discharge current path. . Because it follows the way of the easiest resistance, and thus the low resistance wire.

  Furthermore, the low resistance wires are easy to handle and easy to guide by the guide element.

  The low resistance wire may include a surge current limiting resistor at its free end.

  The surge current limiting resistor ensures that the charge can be discharged. Preferably, a surge current limiting resistor is placed at the free end of the low resistance wire.

  The surge current limiting resistor can be shaped so that it is easily glideed into and out of the guide element.

  Advantageously, the winch is connected to a drive, and the drive may be configured to allow remote control of the winch.

  For example, by using a remote control or another interface, the drive is equipped with a receiver and transmitter so that the operator can extend and retract the winch and thus the extendable grounding device in remote operation. obtain.

  The high voltage valve unit may be a hanging semiconductor high voltage valve structure with at least two valve layers.

  In one embodiment, the electrical shielding structure may comprise a plurality of corona shields disposed around the valve layer of the high voltage valve unit.

  Each corona shield is in electrical contact with at least one of the grounding devices when the stretchable grounding device is stretched. If the corona shields are not electrically interconnected with each other, multiple extensible ground systems can be used to ground all the corona shields.

  In one embodiment, each valve layer comprises an exposed surface, whereby each corona shield is assigned to one exposed surface and a guide element is assigned to each corona shield, thereby lowering the resistance wire. Are guided in a zigzag pattern from the guide element to the guide element. The guide elements assigned to the electrical shield can be a pair of guide elements.

  Thus, as seen in the vertical direction, the first set of guide elements assigned to the first valve layer is shifted slightly horizontally considering the continuous guide elements assigned to the continuous valve layer. Thereby achieving and establishing a zigzag pattern, whereby each electrical shield is grounded.

  Instead of using a funnel shaped guide element, it is also possible to use a magnetic element that is configured to interact with a low resistance wire that has magnetism when stretched. Such a magnetic guide element can physically and thus electrically contact low resistance wires designed to be magnetic.

  A special magnetic contact is installed on the low resistance wire to ensure that the wire is in contact with the magnetic guide element.

  Overall, all terms used in the claims are to be interpreted according to their ordinary meaning in the art, unless explicitly defined otherwise herein. Unless explicitly stated, “one / its elements, devices, components, systems, units, parts, etc.” refers to at least one example of such elements, devices, components, systems, units, parts, etc. Interpreted in a broad sense.

  The present invention will now be described by way of example with reference to the accompanying drawings in which:

1 schematically shows a side view of a hanging valve known to be equipped with an electrical shield. Fig. 2 shows the valve of Fig. 1 looking down from above. 1 schematically illustrates a high voltage semiconductor valve configuration with a grounding system according to the present invention. Fig. 4 schematically shows an embodiment similar to Fig. 3;

  The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which some embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the implementations described herein; rather, these embodiments are rather comprehensive And is provided for illustrative purposes, and fully conveys the scope of the disclosure to those skilled in the art. Similar numbers refer to similar elements throughout.

  The present invention will now be described in more detail with reference to the drawings. 1 and 2 show a high voltage valve configuration comprising a high voltage direct current (HVDC) valve unit 1 ', an external electrical shielding structure 6', and a suspended insulator 8 'carrying the HVDC valve unit 1'. ing. The HVDC valve unit includes a plurality of valve layers 10 '.

  In FIG. 1, the HVDC valve unit 1 'is shown as comprising four valve layers 10'. The valve layer 10 ′ is installed so as to hang from the ceiling 28 ′ of the structure, and they are fixed to the ceiling via a suspended insulator 8 ′. The suspended insulator 8 'is also configured to interconnect the valve layers 10' therebetween.

  The shield structure 6 'includes a plurality of electrical shields 16', such as corona shields 16 '. The electrical shield 16 'is positioned over the exposed surface 38' of the valve layer 10 'so that the field strength is limited to an acceptable level. The HVDC valve unit 1 ′ shown in FIGS. 1 and 2 has a side face with a total of five exposed surfaces 38 ′, ie four side surfaces and one oriented away from the ceiling 28 ′. With a lower surface.

  Each side, and therefore each exposed surface, and each HVDC layer 10 may comprise an electrical shield 16 '. The electrical shields 16 'are not interconnected with each other electrically or otherwise. There is a gap between the electrical shields 16 '. Although not shown in the figure, the upper surface facing the ceiling 28 'may also include an electrical shield.

  As shown in FIG. 2, the valve layer 10 ′ may comprise at least one, two or more valve modules 11. The valve module or unit 11 may or may not be electrically interconnected in the horizontal direction. Reference is now made to FIGS. 3 and 4, which illustrate embodiments of the present invention, in which the high voltage DC semiconductor valve configuration 1 comprises an electrical shielding structure 6, and thus an electrical shield 16 or corona of the shielding structure. A grounding system 4 configured to ground the shield is provided.

  The grounding system 4 comprises an extensible grounding device 12 and a guide element 14 that is part of the guide arrangement. The stretchable grounding device 12 includes a low resistance wire 20 and a winch 26 connected to a drive 22. The winch 26 is attached to the ceiling 28 of the structure.

  The drive 22 is configured to be remotely controlled from a distance so that the operator does not have to step into the valve hole before the corona shield is properly grounded. The drive 22 can be an electric drive 22 or the like that can be easily maneuvered via a remotely located computer or another remote interface. The low resistance wire 20 may be connected to the ground interface in the ceiling 28 via the winch 26. Remote control of the winch 26 is performed either by wireless or wired connection.

  The guide element configuration and the guide element 14 are configured to be electrically connected to the electrical shielding structure 6. Each electrical shield 16 or corona shield is electrically connected to the guide element 14. The guide elements 14 are made from a conductive material or they are at least partially covered using a conductive material. As shown in FIG. 3, the guide element 14 has an upper end 34 and a lower end 36.

  The guide elements 14 have a funnel shape and they can be configured to guide the stretchable grounding device 12. This means that the side surface of a guide element 14 is inclined on at least one side of a pair of guide elements. As shown in FIGS. 3 and 4, a pair of guide elements may comprise one tilted element and the other vertical element. However, it is within the scope of the present invention to use a pair of guide elements with two or more inclined surfaces to guide the stretchable grounding device 12. Both guide elements 14 of a pair of guide elements are electrically connected to corresponding electrical shields 16.

  The guide element 14 is alternatively in the form of a double funnel and is open at the upper end 34 and lower end 36, as shown in the left side of FIG. 3 and FIG. The current limiting resistor 24 can be easily stretched without being crossed or blocked by the guide element 14.

  Each valve layer 10 has a plurality of electrical shields 16 assigned to it, in one exemplary embodiment, one for each side surface of the square HVDC valve unit 2, for a total of four electrical shields 16. However, the lowest valve layer 10 further has a lower surface electrical shield 16 "assigned to it, as shown in FIG. 4. The guide element 14 assigned to one electrical shield 16 of the valve layer 10 is continuous. The guide element 14 assigned to the electrical shield of the valve layer 10 is slightly shifted in the horizontal direction, and the low resistance wire 20 is connected to each guide element 14 in its path to the extended position E; It thus ensures that electrical contact is established with each electrical shield 16. A low resistance wire 20 is best shown in FIG. Id element 14, as a result of being shifted horizontally, according to a zig-zag pattern.

  As shown in FIG. 4, the winch 26 is configured to receive the low resistance wire 20, whereby the low resistance wire 20 is stretched and thus stretched from the retracted or retracted position W, and It is possible to retract or retract from the extended position E and thus be wound up. The low resistance wire 20 may include a surge current limiting resistor 24 at its free end. Surge current limiting resistor 24 is configured to dissipate potential surge currents or some other spontaneous discharge. As shown in FIGS. 3 and 4, the surge current limiting resistor 24 is specially shaped to facilitate the guide of the low resistance wire 20 by the guide element 14. As shown in FIGS. 3 and 4, preferably the surge current limiting resistor 24 is shaped like an arrow or shaped like a double arrow, but allows or facilitates guiding by a guide element. It will be apparent that any other shape may be used and included within the scope of the present invention.

  The grounding system 4 shown in FIGS. 3 and 4 comprises four extendable grounding devices 12, each being arranged on each one of the four side surfaces of the high voltage DC semiconductor valve unit 2.

  The use of only one stretchable grounding device 12 for the high voltage DC valve unit 2 is within the scope of the present invention. However, in one such embodiment, the electrical shields 16 of the electrical shielding structure should then be electrically interconnected between each other.

  The valve layer 10 and the valve module of the HVDC valve unit can be, for example, a mercury arc valve, a thyristor valve, or a transistor.

  As described in FIGS. 1 and 2, the valve layer 10 is connected to the ceiling by the suspended insulator 8, but the valve layer 10 is connected within a range of a scaffold (not shown) that carries the valve. And can be arranged. In one such embodiment, the scaffold may carry the electrical shielding structure 6 and thus the grounding system 4 as well.

  The present invention has now been described by showing how the grounding system 4 interacts with the electrical shielding structure 6 and how the extensible grounding device 12 interacts with the guide element 14. However, the surge current limiting resistor 24 and its shape each establish electrical contact with each electrical shield 16 on one side surface of the HVDC valve unit 2, so that the low resistance wire 20 is Extendable, avoiding guide elements 14 in the grounding system 4 in a manner that ensures electrical contact with each electrical shield 16, 16 "assigned to one side surface and / or lower surface of the unit 2 It is possible to arrange the electrical shield 16 in view of the grounding device 12. The electrical shield 16 is arranged eccentrically and the low resistance wire 20 is on its path from the retracted position W to the extended position E. , And when in position E, ensure that contact is established with each electrical shield 16 on one side surface of the valve unit 2.

  Instead of the surge current limiting resistor 24, a normal element made of conductive material is used to guide the low resistance wire 20, provide some weight to straighten the wire 20, and extendable ground It should be noted that the extending and retracting operations of the device 12 and the low resistance wire 20 can be facilitated, respectively.

  A surge current limiting resistor 24 is disposed at the free end of the extendable grounding device 12. The surge current limiting resistor 24 first establishes electrical contact with the guide element 14 and thus the electrical shield 16 when the extendable grounding device 12 is moved from the retracted position W to the extended position E. Configured to be the first element or portion of the stretchable grounding device.

  The stretchable grounding device 12 has been described and illustrated by a winch 26, a drive 22, and a wire 20. Configured to establish electrical contact with the electrical shield 16 assigned to one side surface of the valve unit 2 when in the extended position E and their path from the retracted position W to the extended position E Any other suitable stretching device that can be used for grounding, such as a stretchable and retractable spring system, a stretchable and retractable scaffold structure, or just a stretchable and retractable telescoping configuration Use is within the scope of the present invention.

  The grounding system 4 grounds only the external electrical shielding structure 6 and does not ground the HVDC valve unit 2 itself.

  Instead of using a hanging high-voltage valve configuration 1 with a suspended insulator 8, it is possible to install a high-voltage valve configuration 1 that stands on the valve hole floor 30 of the structure or valve hole. In one such embodiment, the stretchable grounding device 12 is a fixed stretchable grounding such as a scaffolding structure that can be stretched or a telescoping stretchable device that can be stretched from the valve hole floor 30 toward the ceiling 28. It can be a device. Such a grounding device 12 also comprises a surge current limiting resistor at its free end, ensuring that this resistor is initially the first element that establishes electrical contact with the guide element 16. To do.

The present invention has been described above primarily with reference to several embodiments. However, as will be readily appreciated by those skilled in the art, other embodiments different from those disclosed above are equally possible within the scope of the invention as defined in the appended claims.

Claims (11)

High voltage valve unit (2),
At least partially arranged, external electrical shield structure around the high conductive 圧Ba Lube unit (2) (6),
A grounding system comprising a stretchable grounding device (12) disposed on a side surface of the high-voltage valve unit and configured to be remotely stretched in a vertical direction from a retracted position (W) to an extended position (E); 4) when the extendable grounding device establishes an electrical connection with the external electrical shielding structure (6) when extended from the retracted position (W), and the extendable grounding device ( 12) is a grounding system configured to be attached to the ceiling (28) of the structure, and a plurality of guide elements (14) electrically connected to the external electrical shielding structure (6) A plurality of extendable grounding devices (12) configured to establish an electrical connection with at least some of the guide elements (14) when in the extended position (E); With a guide element, High voltage valve configuration (1).   The extendable grounding device (12) extends vertically downward (A) from the retracted position (W) to the extended position (E), and vertically upwards (A) from the extended position (E) to the retracted position (A). The high voltage valve configuration of claim 1, wherein the high voltage valve configuration is configured to be mounted to retract to ').   The high voltage valve arrangement according to claim 1 or 2, wherein at least some of the guide elements (14) are funnel shaped.   The high-voltage valve arrangement according to claim 3, wherein at least some of the guide elements (14) are funnel shaped at both ends and thus extend at the upper end (34) and the lower end (36) rather than in the middle. .   The high voltage valve arrangement according to any one of claims 1 to 4, wherein the stretchable grounding device (12) comprises a surge current limiting resistor (24) disposed at a free end of the stretchable grounding device. . The stretchable grounding device (12) comprises a low resistance wire (20) and a winch (26), the low resistance wire (20) being wound up by the winch (26), wherein the winch is retracted. 6. The high voltage valve arrangement of claim 5 , configured to move the low resistance wire from position (W) to the extended position (E) and vice versa. The high voltage valve arrangement of claim 6 , wherein the low resistance wire (20) comprises the surge current limiting resistor (24) at a free end of the low resistance wire.   A high voltage valve arrangement according to claim 6 or 7, wherein the winch (26) is connected to a drive (22) configured to allow remote control of the winch (26). 9. The high voltage valve arrangement according to claim 6 , wherein the high voltage valve unit (2) is a hanging semiconductor high voltage valve structure with at least two valve layers (10). The high electrical shielding structure (6) according to claim 9, wherein the external electrical shielding structure (6) comprises a plurality of corona shields (16) arranged around the valve layer (10) of the high voltage valve unit (2). Voltage valve configuration.   Each valve layer (10) includes an exposed surface (38), each corona shield (16) is assigned to one exposed surface (38), and a guide element (14) is attached to each corona shield (16). Assigned, whereby the low resistance wire (20) is guided by the guide element (14) in a zigzag pattern from the guide element (14) to a continuous guide element (14 '). High voltage valve configuration as described in.

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